Problem: Simplify the following expression: ${6(5r-11)-(5-r)}$
Explanation: Distribute the ${6}$ into the first set of parentheses: $ {6(}\gray{5r-11}{)} - (5-r) $ $ {30r-66} - (5-r) $ The minus sign in front of the parentheses means we multiply each term inside the parentheses by ${-1}$ $ 30r-66 {-1(}\gray{5-r}{)} $ $ 30r-66 {-5+r} $ Rewrite the expression to group the ${r}$ terms and numeric terms: $ {30r + r} {-66 - 5}$ Combine the ${r}$ terms: $ {31r} {-66 - 5}$ Combine the numeric terms: $ {31r} {-71}$ The simplified expression is $31r-71$